PROJ02232 - Laserfiche WebLink

Home Browse Search

Tributarv Areas. LAWMA covers 51 irrigation wells and 24 municipal wells and commercial wells in the tributary areas, primarily the Big Sandy and Two Butte Creeks basins. Two Butte Creek joins the Arkansas River at Holly, downstream of any Colorado ditch. The confluence of Big Sandy Creek and the Arkansas River is located about 8.5 miles upstream from the Buffalo Canal diversion. Big Sandy Creek normally is intemuttent except during major precipitation events. The stream flow during these events is reduced by an amount of additional groundwater rechazge induced by the well pumping. Otherwise, the pumping afFects evapotranspiration (ET) by native vegetation in the creek valley. The depletions with respect to the Arkansas River from LAWMA member well pumping in these tributary areas were estimated to be equal to 4% of the wellhead depletions on an annual basis (1996, Helton and 1997, Helton) and are replaced to the Arkansas River. The pumpage from the tributary areas totaled 2,560 acre-feet in 2006, representing 71 acre- feet of potential depletions. 6,215 acre-feet of pumping is a good estimate of future average pumpage in the tributary areas by LAWMA's present membership. Mainstem Municipal Wells. The City of Lamar has a well field in the Clay Creek basin a tributary of the Arkansas River. The City conveys water obtained from the Southeastem Colorado Water Conservancy District ("SECWCD") and from its ownership of shares of stock in the Fort Bent Ditch Company through the Fort Bent Canal to a recharge site on Clay Creek. Such deliveries are generally sufficient to replace the City's depletions. The Lamar Light & Power wells are used to cool the generation equipment at the Lamar Powerplant. Depletions are not charged against the Lamar Light and Power wells as the cooling system is fully contained and the heated water is discharged to the Lamar Canal and charged against the Lamar Canal decrees. The municipal wells used by the May Valley Water Association, Town of Wiley, Town of Granada, Town of Holly, Hasty Water Company, and McClave Water Association derive their supplies from the non-tributary Dakota and Cheyenne aquifers and are not subject to the Arkansas River Use Rules. The Granada School District, Lamar Community College, and Prowers County Courthouse are considered municipal members, but their wells are used strictly for urigation purposes and their pumpage is included with the irrigation pumpage estimates. Mainstem Irri�ation. The mainstem irrigation well pumpage for LAWMA members is summarized in the table below for 1997 through 2006.